"He came the first day and parked outside the hotel and asked me to watch over his car. He then left after having coffee and gave me KSh 100. He is huge and heavily built," the eyewitness told journalists.

Following the incident, security apparatus are on high alert and are coordinating the rescue and evacuation mission.

The police managed to isolate one vehicle believed to have been used by the attackers to access the area.

TUKO.coke earlier reported a number of people were held up inside neighbouring office complex and the 5-star DusitD2 hotel.

It is claimed one of the attackers hurled a grenade at the vehicles in the parking sparking the fire which consumed the three cars right in front of the hotel entrance.

The area remains cordoned off even as police advises motorists to use alternative routes for easy rescue operations.

Earlier on, sources told TUKO.co.ke the attack has been classified as a terror attack but the same has not been made official.